In many welding operations used heretofore when a plurality of parts are to be welded together, various clamping mechanisms have been employed to position and hold the stampings together until the welding operation was completed. In conventional systems used heretofore, fixtures for holding the stampings have generally been extensive and costly. Generally, lines and valve units were required to control the sequence of steps throughout the welding operation.
In the past systems, an excessive amount of operator time was required to place, locate and load the clamps which were relatively large and generally included several pieces of steel welded together. This type of assembly fixture with extensive use of clamps adds higher costs to the overall production operation.
Programmable machines are well known. Such machines have been used to move parts to different positions, and also to control welding operations. One such machine is disclosed in a patent to Hohn #4,011,437. In this and other programmable systems all pieces or components are moved from one station to another where different operations are performed.
Many systems are programmed to perform particular movements and particular operations. Generally, if the movements or operations are revised or modified due to product modification or different assemblies of parts extensive time and costs are involved to make changes in the manufacturing system. For example, when a product change requires a change in one or several stampings within an assembly, modifications to the fixture must be made. Also material relating to the change generally involves relocation of pneumatic clamps, nesting gauges and other equipment to accommodate the different parts and welding pattern changes.